Check your pulse if you don’t feel a chill winding between your vertebra during a scene in “Martha Marcy May Marlene” where Academy Award-nominated actor John Hawkes (“Winter’s Bone”) sits among a commune of vulnerable, lost souls and proceeds to serenade them with “Marcy’s Song,” a previously unreleased track on folk musician Jackson C. Frank’s eponymous 1965 album. It’s a hauntingly beautiful moment in the indie thriller that confirms just how absorbed one can become when looking for something tangible to believe in. The soft-spoken lyrics suggest a fine line between dreams and reality as he sings about a girl he loves who no longer exists to him anymore. As lead title character Martha, actress Elizabeth Olsen stares intently as if no one else is listening. Her fascination is palpable with every strum on his guitar. You can only wonder how many others have fallen victim to his siren song.

As a member of a highly-persuasive rural cult, Martha (AKA Marcy May) is easily captivated by their customs, but eventually makes her escape and reaches out to her estranged sister Lucy (Sarah Paulson). Lucy and her husband Ted (Hugh Dancy) haven’t seen Martha in years, so when they get a phone call from her asking to pick her up at a remote location, Lucy doesn’t hesitate and opens her lakefront home to her troubled sibling.

It’s not as easy, however, as giving her a bed to sleep in or food to eat. Martha has issues and her paranoia runs deep. Unlike Natalie Portman in “Black Swan,” who can’t get a handle on her psychosis, Martha’s problems stem from something more concrete. Her emotionally-damaged psyche triggers a disconnection from the real world and, in turn, forces her to relive her time in the cult through flashbacks and creepy nightmares. It’s during these unnerving instances, masterfully edited by Zachary Stuart-Pontier (“Catfish”), which gives Martha a jolt into a narrative more complex than just a typical crazy-girl nail-biter.

Directed and written by first-time feature filmmaker Sean Durkin, Martha is relentless with its unsettling tone, which is always at a feverish level. Durkin makes bold choices in the nonlinear way he decides to tell his story, but each scene is crafted with such precision, the extra work spent on experimenting with timelines seems effortless.

Then there’s Olsen, whose breakout performance is the most inspired we’ve seen since Jennifer Lawrence’s Oscar-nominated turn in “Winter’s Bone” last year. It’s a stunning debut that elicits fear, anxiety, and mental anguish within one girl’s fragmented state of mind.